1. Technical Field
The present invention relates to sensors.
2. Related Art
Sensors are known that acquire, from a distance, the temperature history of an environment in which goods are placed while those goods are being transported or stored. Such sensors are used to ascertain whether, for example, frozen food or the like has been kept in its frozen state until its arrival at a retail store or the consumer.
A technology has been proposed, in which this type of sensor is combined with an IC tag, and data representing the temperature history measured with the sensor is stored in the IC. However, with this system, the data representing the temperature history is stored as electronic data, so that there is the risk that the data is tampered with.